In 2017, natural gas provided 32% of the total electricity generation in the United States, taking over coal with 30% of the share. When comparing electricity generation sources by state, fossil fuels continue to be the most common source in 35 states in 2017. Compared to 2007, this number is down from 40 states using the mainly fossil fuels for power generation.

The following chart shows the changes in the number of states and the most common sources of electricity generation for each state:

Number of States Using Main Electric Generation Sources

Electricity Generation Source

2007

2017

Coal

28

18

Natural Gas

11

16

Petroleum

1

1

Nuclear

6

9

Hydro

4

6

With the retirement of coal-fired power plants, the 10 states that were primarily generating electricity from coal in 2007 converted either to natural gas or nuclear. Vermont ‘s sole nuclear power plant was retired in 2014, and hydro and biomass became the state’s power generation sources. In Maine, the decreased use of the state’s natural gas-fired generator resulted in hydro becoming the state’s most common power generation source. New Jersey increased their natural gas power generation by more than 25%, thus surpassing nuclear as the main power generator.